Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Carrying Amount
Investment in receivables, net
Investment in receivables, net	$ 9,611	$ 18,348
Carrying Amount | Senior secured revolving credit facility
Debt
Revolving credit facility	165,000	155,000
Carrying Amount | Secured notes
Debt
Secured Notes, net	222,752	223,685
Fair Value
Investment in receivables, net
Investment in receivables, net	9,990	18,867
Fair Value | Senior secured revolving credit facility
Debt
Revolving credit facility	165,000	155,000
Fair Value | Secured notes
Debt
Secured Notes, net	$ 224,511	$ 224,333